In this project, we are developing an adhesive bandage with built-in genetically modified yeast. It is intended to be used by patients with bedsores to monitor the condition of the wound while it heals. In Japan’s aging society, reducing the burden of pressure ulcer treatment is of great significance. The main objective of our project is to make home medical care more manageable and to reduce the burden on care workers by making it possible for anyone to detect the condition of bedsores.
In order to implement this project to society, we have to clear some safety barriers. We will also propose a solution for them.

Purpose of the implementation

In Japan, pressure ulcers caused by obesity are rare, and those caused by bedridden elderly people and diabetics tend to be more common. Therefore, we surveyed the needs of pressure ulcer treatment in Japan by interviewing the families of patients, nurses, and specialists in our Human Practices.
In response to the emerging issues of pressure ulcer care which we learned from the Integrated Human Practices, our project presents the following solutions:

There is a shortage of doctors who expertise in pressure ulcers, especially in rural areas.
→By making it easier to understand what is needed in the current bedsore condition by changing the color of the bandage, we will make it possible to proceed with treatment even if the doctor is not specialized in bedsore treatment.

In-home medical care, even a small thing such as frequent visits of a nurse to the house or limited privacy of the patient’s family, is a big mental burden.
→Our device enables the family members to manage the patient’s condition without calling the nurse frequently.

In the case of the elderly whose immunity has been weakened, even if a wound is infected, inflammation does not occur and it may not be apparent at first glance.
→Based on this opinion, we adopted an infection detection system. It enables us to easily check for infection without the use of special equipment.

Some people are allergic to existing antibacterial agents such as silver and iodine
→Human-derived defensins, antimicrobials themselves are less likely to cause allergies.

Regulations on GMOs

How are GMOs regulated in Japan?

Based on the Cartagena Protocol on Biosafety, There is a law that regulates the use of GMOs in Japan(Law Concerning the Conservation and Sustainable Use of Biological Diversity through Regulations on the Use of Living Modified Organisms).
This law stipulates two types of use of genetically modified organisms.

(1) Type 1 use
Use without preventing the spread of GMOs into the environment
(2) Type 2 use
Use with measures to prevent the spread of GMOs into the environment

In the case of our project, even if we take measures to prevent proliferation with kill switches, etc., the public will use the genetically modified product in an environment that is not necessarily properly controlled. We believe that it is realistic to obtain a permit under the category of Type 1 use while trying to prevent proliferation as much as possible. The approval procedure for Type 1 use is as shown in the figure below.

In Japan, GMOs have never been built alive in devices in the medical field so far, as they are mostly used in the production of substances. Therefore, our bandage would be necessary to pass a strict screening process as a new case in order to reach practical use. We were told from a company we interviewed for financial reasons that currently there is a trend in Japan to positively consider the use of genetically modified organisms in medical devices. We believe there is a good chance that the approval will be granted, although it may take some time.
Another possible way to meet the national standard is to use a cell-free system, a strategy that does not use genetically modified organisms. In this case, the hurdle is expected to be a little higher, as a more advanced semipermeable membrane will be needed to prevent the contents from leaking out.

Other hurdle for implementation

In addition to the use of genetically modified organisms, there are other safety and functional points that need to be addressed in the future.

Can the hardware prevent the entry of oxygen?

The wound dressing we have developed monitors the degree of wound healing by detecting the oxygen concentration. For accurate detection, it is necessary to shut the air off from the bandage so that the oxygen outside does not affect. We believe that the hardware to achieve this function will be necessary for effective monitoring of wounds..

Will the secretions from the yeast cause allergies?

In addition to defensins, yeasts also secrete a variety of other substances extracellularly, and some of them will likely pass through the cell fiber. For example, ethanol will be produced by anaerobic respiration by yeast. It is necessary to conduct animal experiments and clinical trials to verify that these substances do not cause allergic reactions or other adverse effects.
In principle, there is no leakage of yeast cells or proteins with large molecular weight out of the cell fibers. Of course, the durability of the cell fibers should be thoroughly tested for safety.

  1. 1.National center for child health and development , Commentary on the description of the Biodiversity Impact Assessment, 2007.
  2. 2.Ministry of Agriculture, Forestry and Fisheries, Conceptual diagram of application, approval/confirmation, inspection, etc. for use of genetically modified organisms based on the Cartagena Act, 2021.